cisco, linux, networking, security, windows

ACS 5.8 to ISE 3.0 migration: The server selected protocol version TLS10 is not accepted by client preferences [TLS12]

by tini

Tried to migrate ACS 5.8 to ISE 3.0 but I was getting following message: “The server selected protocol version TLS10 is not accepted by client preferences [TLS12]”.
Since TLS 1.0 is disabled by default I had to enable it in java control panel (Oracle java 1.8) and also edit file C:\Program Files (x86)\Java\jre1.8.<some_version>\lib\security\java.security, remove TLSv1 from option jdk.tls.disabledAlgorithms and finally restart the migration application.

You can do the same in linux environment for openjdk by editing /usr/lib/jvm/java-11-openjdk-amd64/conf/security/java.security

Tnx to stackoverflow

cisco, linux, networking

Connect to Cisco device with USB cabel on linux

by tini

user@computer:~$ dmesg | grep tty
[ 0.088345] printk: console [tty0] enabled
[ 0.418156] serial8250: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
[ 5.030307] usb 1-3.1.3: pl2303 converter now attached to ttyUSB0
[86188.149229] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
[86271.641530] usb 1-2: pl2303 converter now attached to ttyUSB0
[86796.881771] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
[86855.323347] usb 1-4: pl2303 converter now attached to ttyUSB0
[86877.932139] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
[86884.784432] usb 1-4: pl2303 converter now attached to ttyUSB0
[87068.706927] pl2303 ttyUSB0: pl2303_set_control_lines – failed: -19
[87068.706937] pl2303 ttyUSB0: error sending break = -19
[87068.707250] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
[259915.126314] cdc_acm 1-3.1.3:1.0: ttyACM0: USB ACM device

linux, networking, security

SSH not working after upgrade

by tini

I upgraded ubuntu to focal 20.04 and SSH was unable to negotiate with network devices I tried to ssh on.
Solution was found here, or simpy editing /etc/ssh/ssh_conf by adding following lines to the end of the file:

Ciphers aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc
MACs hmac-md5,hmac-sha1,umac-64@openssh.com
KexAlgorithms diffie-hellman-group1-sha1,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1
HostKeyAlgorithms ssh-rsa,ssh-dss